Early results from our research group have suggested that SIMS ion emissions code information related to molecular mobility. We have been looking for well characterized systems to test these ideas out, and have found such systems in the laboratory of Professor Galiatsatos. He synthesizes "perfect" poly(dimethyl siloxane)(PDMS) networks which use tetrachlorosilane to achieve tetrafunctional chain junctions. As the molecular weight of the oligomers that are crosslinked are tightly controlled, a network is created that is well understood, and behaves according to accepted gel swelling theories. By controlling the molecular weight of the PDMS precursors, the crosslink density is varied. As well as SIMS studies on these polymers, Professor Galiatsatos will attempt to model the SIMS data using molecular dynamics methods.